1. Field of the Invention
The present invention relates to a perpendicular magnetic write head having at least an induced magnetic transducer for recording, a method of manufacturing the same, and a method of forming a magnetic layer pattern.
2. Description of the Related Art
In recent years, as surface recording density of a magnetic recording medium such as a hard disk (hereinbelow, simply called “recording medium”) improves, improvement in the performance of a thin film magnetic head mounted on a magnetic recording apparatus such as a hard disk drive is in demand.
As recording methods of the thin film magnetic head, a longitudinal recording method of setting the direction of a signal magnetic field to the in-plane direction (longitudinal direction) of a recording medium and a perpendicular recording method of setting the direction of a signal magnetic field to a direction orthogonal to the surface of a recoding medium are known. Recently, the perpendicular recording method is widely employed in place of the conventional longitudinal recording method for the following reason. In the perpendicular recording method, advantages are obtained such that higher line recording density is obtained and a recording medium on which data is recorded is not easily influenced by heat fluctuation.
A thin film magnetic head of the perpendicular recording method (hereinbelow, simply called “perpendicular magnetic write head”) has a thin film coil for generating a magnetic flux and a main magnetic pole layer for guiding the magnetic flux generated by the thin film coil to a recording medium.
A perpendicular magnetic recording head in which the main magnetic pole layer extends in the direction crossing the air bearing surface is known. The head structure of this kind is generally called a “single magnetic pole head”. A single magnetic pole head in which an auxiliary magnetic pole layer for supplying magnetic flux is provided as well as a main magnetic pole layer in order to increase the intensity of a magnetic field (perpendicular magnetic field) for recording is developed (refer to, for example, Japanese Unexamined Patent Application Publication Nos. H02-066710 and 2002-197615). However, it is said that the single magnetic pole head has limitation in improvement in the recording density of a recording medium.
Recently, a perpendicular magnetic write head having a write shield layer for capturing a spread component of a magnetic flux emitted from a main magnetic pole layer in order to further improve recording density is becoming mainstream. The head structure of this kind is generally called a “shield head”. A shield head in which a write shield layer is disposed on the trailing side of the main magnetic pole layer is developed (refer to, for example, U.S. Pat. No. 4,974,110 specification and European patent application publication No. 0360978 specification).
In particular, another shield head is also developed in which, to suppress unintentional erasure of information recorded on a magnetic recording medium at the time of recording, an auxiliary magnetic pole layer is provided on the trailing side of a main magnetic pole layer (refer to, for example, U.S. Pat. Nos. 7,433,152 and 7,457,080 specifications).
Higher recording performance of the perpendicular magnetic recording head is in increasing demand. In consideration of this situation, recently, new proposals are being made as measures to improve the recording performance. For example, an attempt is made to reduce a leak magnetic flux and to improve the intensity of a recording magnetic field arriving at a magnetic recording medium by forming a main magnetic pole layer including an inclined face obtained by gradually decreasing the thickness of the main magnetic pole layer toward a recording medium facing surface (refer to, for example, Japanese Unexamined Patent Application Publication No. 2005-293822).